Many tools are powered by pneumatic air or hydraulic fluid that provides the necessary pneumatic or hydraulic power to the tool. Impact wrenches, for example, can use pressurized air to impart torque to a work piece to loosen or tighten the work piece. At times, the rotational direction of the tool must be reversed, for example, when the work piece is left-hand threaded or when the user wishes to tighten the work piece instead of loosen it with the power tool.
Existing pneumatic and hydraulic tools include reversing mechanisms that selectively control the rotational direction of the tool. In some conventional pneumatic or hydraulic tools, the reversing mechanism is located on the rear of the tool, and can be a rotational knob that the user can use to select the desired rotational direction of the tool when rotated accordingly. In other tools, the reversing mechanism is an axially depressible button that changes the rotational direction of the tool by directing air or fluid in either of the clockwise or counterclockwise directions. These reversing mechanisms, however, are also typically located on the rear of the tool or in an otherwise hard to reach place, and not ergonomically located near the user's fingers during use of the tool, for example, near a trigger that causes the release of pressurized air or fluid. Such a location typically requires the user to disengage the tool from a work piece to change the rotational direction of the tool.